The school playground can promote PA for large numbers of children. This study identifies areas of the playground that children visited at break-times, the decisions according to gender and the influence of contextual and environmental variables on PA levels. The playground of a culturally diverse primary school was observed during morning break-times and lunchtimes. Counts of sedentary, LPA, and MVPA episodes, and the contexts in which they occurred were recorded using the system for observing play and leisure in youth (SOPLAY). Ball sports areas had higher counts of boys (mean ± SD; 9.9 ± 4.8) compared to girls (2.0 ± 3.5); areas promoting climbing and social interaction had higher counts of girls (7.9 ± 7.2) compared to boys (3.5 ± 2.9). The proportion of MVPA episodes during break-times was 34% ± 26%. Areas of the playground with organised activities had 2.70 (95%CI: 1.87 to 3.91) times higher MVPA counts than areas “not organised”. Areas with “supervision” were associated with higher MVPA counts (1.34; 1.18 to 1.53) compared with “not supervised” areas. Organisation and supervision might influence PA choices and PA levels of children in the primary school playground. Further investigation is required to explore different playgrounds settings, and context and gender preferences.